Opening of the New World, with its valuable minerals, was an event on the magnitude of the more recent discovery of atomic power. Each advancement was kept a closely guarded secret so rival nations could not steal information which was altering old balances of power.

Spain claimed all the New World by right of discovery and the blessing of the Roman Catholic Pope. The Portuguese, English and French, however, were determined to share the prize.

Portugal had declined to back Columbus in favor of pushing Vasco Da Gama's well advanced search for a route to China around Africa. Now it was anxious to participate in what might be a shorter way.

When Spain and Portugal appeared about to come to blows over their territorial ambitions, Pope Alexander VI in 1493 divided the non-Christian world between them. His Holiness drew a line in the Atlantic Ocean very soon after Columbus' discovery became known. The western half of the world, including the Americas yet to be fully known, was reserved for Spanish exploitation. Asia and everything east of the line belonged to Portugal.

The principals were not satisfied with the division. Each also wanted a piece of the action in the other's sphere of influence. The following year, therefore, Spain and Portugal agreed in the Treaty of Tordesillas to shift the demarcation line circling the Earth 350 leagues west of the Cape Verde Islands. This gave Spain A toe-hold in China and gave Portugal a limited opportunity to search the South Atlantic.

What the Portuguese lacked in priority they made up in boldness and tenacity. After Vasco da Gama returned in 1499 from his historic voyage to India, around the Cape of Good Hope, King Emanuel dispatched a follow-up fleet. Pedro Alvares Cabral sailed southwest to the treaty limits and planted the flag of Portugal on the tip of Brazil in 1500. With this, Cabral reshaped his course for Africa's cape and India, but he had established a claim for a large chunk of the New World.

England disdained the efforts of the two large maritime nations to carve up the world and launched its own voyage of discovery.

Giovanni Caboto, whom the English called John Cabot, was an Italian navigator like Columbus. Cabot, too, tried to promote a straight-west voyage to Cathay.

Unfortunately he approached King Henry VII who was busy uniting quarrelsome British clans into a nation.

Thus, it was not until 1497 that Cabot obtained a ship and patent to try and accomplish what Columbus failed to do.

Cabot sailed from Bristol on May 20 with three of his sons and said he bumped into a continent at latitude 57°33'. He explored a large stretch of unknown coast which most researchers believe was Maine, Nova Scotia and Labrador. His youngest son, Sebastian, 14 at the time, wrote years later that they rounded the cape of Florida and "put the island of Cuba off the left." However, the round trip required only 77 days, and it is highly improbable that Cabot got any farther south than Maine.

In addition to the historically known mariners churning the Caribbean, we know that slavers plied their trade there to supply the plantations and mines of new Spanish colonies. The small Taínos Indians that Columbus met quickly succumbed to European diseases and unaccustomed hard labor. The stronger Caribs, Canibales, and possibly Calusa, were pressed into service until they, too, died and were replaced finally by sturdy Africans.

This commerce in human labor — officially prohibited but tacitly overlooked — sent slave dealers ranging widely. Ponce de Leon met up in Florida with escaped slaves, possibly from his own plantations, who shouted insults at him in Spanish. These slave expeditions, of course, were clandestine. What charts existed for such raids were guarded by ship captains and eventually destroyed as incriminating evidence.

Columbus had introduced the ancient but nasty practice into the New World to provide some monetary return for his sovereign's investment. When the fortune hunters who followed in the Admiral's wake failed to find gold, they turned also to slave sales to recoup their losses.

MYSTERY BEGINS

There is little doubt that the opportunity to discover North America existed for several explorers during the eight years preceding publication of the first map. Our mystery begins with this unique document drawn by Juan de la Cosa in 1500. It is emphasized that this respected navigator is not the mutinous Cosa who abandoned the Santa Maria during Columbus' first voyage.

The Cosa map is believed to include information from the Columbus, Cabot, Ojeda, and Corte Real expeditions. In turning over his sketches to Spanish authorities, Cosa grumbled about "unauthorized visits" by other explorers.